Method _setupHandlerIfNeeded

packages/rest/src/rest.server.ts:398–418

()

  }

  protected _setupHandlerIfNeeded() {
    if (this._httpHandler) return;

    // Watch for binding events
    // See https://github.com/loopbackio/loopback-next/issues/433
    const routesObserver: ContextObserver = {
      filter: binding =>
        filterByKey(RestBindings.API_SPEC.key)(binding) ||
        (filterByKey(/^(controllers|routes)\..+/)(binding) &&
          // Exclude controller routes to avoid circular events
          !filterByTag(RestTags.CONTROLLER_ROUTE)(binding)),
      observe: () => {
        // Rebuild the HttpHandler instance whenever a controller/route was
        // added/deleted.
        this._createHttpHandler();
      },
    };
    this._routesEventSubscription = this.subscribe(routesObserver);

    this._createHttpHandler();
  }

  /**
   * Create an instance of HttpHandler and populates it with routes